1. Field of the Invention
The present invention generally relates to the Long Term Evolution (LTE) of the 3rd Generation Partnership Project Protocol Release 8 (3GPP) and, in particular, to the transmission of transmission power control (TPC) command signaling in a down link control channel (DL-CCH), to user equipment (UE).
2. Description of the Related Art
In 3GPP, the evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (e-UTRAN) has been defined and is currently being used for the LTE system. UE operating in e-UTRAN or a LTE network may obtain communication services according to the current 3GPP standard. In this regard, for both networks, the 3GPP standard specifies radio system parameters, data transfer procedures, protocols, control messages and bearer traffic exchange over the air interface.
e-UTRAN architecture collectively includes at least one base transceiver station (e-NodeB), and at least one UE. The RAN architecture provides connectivity between the UE and a core network, transmitting many traffic types from real-time circuit switched to internet protocol-based packet switched communication.
In a currently adapted approach in 3GPP, a downlink grant via a Physical Downlink Control Channel (PDCCH) may include the TPC command signal for a Physical Uplink Control Channel (PUCCH), and an uplink grant via the PDCCH may include the TPC command signal for a Physical Uplink Shared Channel (PUSCH).
The TPC command signal may be included in three different DL-CCH file formats, e.g. format 0, format 1, and/or format 2, in the downlink grant via the PDCCH. The TPC command signal may be included in one DL-CCH file format, e.g. format 0, in the uplink grant via the PDCCH.
However, because scheduled downlink and/or uplink transmissions may occur infrequently, UE may not receive necessary TPC command signaling for controlling the transmission power of the PUCCH or the PUSCH.